Automatically-balanced vertical-shaft centrifugal pump.



No. 865,900. PATENTE D SEPT. 10, 190?.

A. W. HUNSAKER. AUTOMATIUALLY BALANCED VERTICAL SHAFT GENTRIFUGAL PUM PPLICATION FILED APR.19. 1905.

ARCIIIBALD W. I-IUNSAKER, OF POMONA, CALIFORNIA.

AUTOMATICALLY-BALANCED VERTICAL-SHAFT (JENTRIFUGAL P'Uh'lil.

Specification of Letters Patent.

Fatented Sept. 10, 1962' Application filed April 19, 1905. Serial No. 256,?73-

To all whom it may concern:

Be it known that I, Anonnmnn Wronrnnn Hunsnunn, a citizen of the United States, residing at Po niona, in the county of Les Angclcs, in the State of California, have invented an Automatically-Balanced Vertical-Shaft Centrifugal Pump, of which the following is a specification.

An object of the invention is to provide novel improved means to balance the impeller and shafting against end thrust in a centrifugal pump in which the suction or intake enters at the bottom of the pump shell.

Another object is to provide a water bearing for limiting the upward movement of the impeller.

An object of this invention is to avoid the trouble which arises from the admission of air to the impeller in that form of balanced centrifugal pumps in which the suction is taken in at the top.

An object of this invention is to provide an automatically balanced centrifugal pump which will keep itself free from accunuilations of sand, and in which the suction is so arranged as to draw the sand away from the working parts.

Another object is to provide a balancing device for centrifugal pumps free from complicated valves, piston leathers, packing rings, or other close fitting bearings; also to provide a pump that obtains its balance from either the pressure of the water in the discharge pipe, or from the vacuum pressure created by the suction, or from both, and in which the balance remains cll'ectual whether the pump is working to its full capacity or not.

This invention relates to a vertical pump, and in practice, the impeller of such a pump is driven by power received from a shaft extending downwardly to the impeller from power which. in the case of pumps uscd in wells, is located at the surface of the ground, while the pump is located below the surface of the ground. In the following specification, therefore, it is to be understood that by the term top I mean that sido'ot the runner or impeller into which the shaft extends from the motor, not shown; and that by the term bottom I mean that side of the runner or apparatus underneath or opposite that portion of the driving shalt through Whichthe power is applied to the impeller.

Heretolore, there have been bottom intake pumps in which external devices, such as valved or pistons, have been employed to assist in balancing or'carrying the weight. of runner and shatting. Other centrifugal pumps have been provided with an intake around the shalt through which the power is applied to the impeller, and on the same side of said impeller with the motor which drives the impeller; that is to say, on

the top of said impeller when said pump is installed, so that the shaft stands vertically above the impeller. In other instances, centrifugal pumps have been installed with the power shaft horizontal and the intake entering at the side of the impeller, as distinguished from the bottom of the impeller. This invention is distinguished from all such constructions by having the intake vertically below the vertical shaft through which the power is received lrom above.

The accompanying drawings illustrate the invention.

Figure 1 is an axial section on line XX Figs 2. Fig. 2 is a plan section on line ji -X Fig. 1.

The outlines of the several heads are indicated by dotted lines.

l is a shell having a bottom intake 2 and a peripheral outlet 3, and provided at the top with a suction-ehamber 4, connected withand of greater cross-sectional area than the intake 2.

5 is a centrifugal impeller of the closed type, fur nished with a head 6 working in the suction-chamber 4, and with ahead '7 working in the intake 2, the impeller being imperforatc throughout the portion thereof Within the periphery of the last-named head 7. The suction-chamber 4 and the intake 2 are connected by a by-pass 8. The lower head 7 oi the rotary impellet is openended, is mounted axially above the open intake 2, and is open axially directly from the intake 2 and into the interior of the impeller communicating with the peripheral outlets "thereof.

9 is a shaft which carries and drives the impeller 5,

said shaft being ordinarily {when not running) supported at the top by a collar (not shown) in the usual way to hold the impeller clear from the bottom of the shell when not in operation, and before the balance takes effect. The by-pass 8 enters the suction-chamber 4 at a port 10, which opens into an upwardly-extending annular offset 11 of the top oi the chamber 4. Said offset is concentric with the shaft 9.

12 is an upwardlyextending throttling offset on the head 6, adapted to enter the ohset ll, thus regulating the size of the passage leading into by-pass 8 between the pressure-chamber 4 and the intake 2 before the head 6 comes to the top of thesnctihn-chamber t on the up-thrust oi the impeller.

to automatically establish an equilibrium between the weight of shaiting, and impeller and the weight of suction and discharge water." The shell 1 is also provided between the intake 2 and the outlet 3 with a lower pressurc-chamber l3, and is provided in its top with a prcssurerhamhcr l4. Said pressure-chambers are connected with the outlet 3, and the upper one, 14, is of less cross-sectional area than the lower one, 13. The impeller 5 is pmvidcd with heads 15 and 16 work- 12 practically. forms a valve head or throttle for controlling the by-pass 8 in; respeetively in the pressure-ehamhers 14 and 13. The chambers l3 and H open to the peripheral outlet 3 as indicated at l7 and lh' so that wheneverthe pressuperficial area than the top head 15 there is an exees: of upward pressure applied to the head 16 to serve toward eounterlmlaming the weight'of the. shaft 5) and impeller 5.

20 is a priming pipe with valve 2] for (losing the same, whieh will be eonveniently placed within reaeh of the operator.

In starting thepnmp into operation it will be primed in the usual wa v, and when the sttetion-heeomes el'l'eetive it operates through the by-pass \Sinee the superficial area of the head t is greater t lta that of suetion pipe 22, the effect, as is well known is to eounterbalance tlte weight. of the impeller and its shalt it to the extent of the ditierenee of areas nntltiplied by the pressure per square llt('lt.- \VIn-never the innpeller is raised sullieiently to bring, the.ot'lset or Valve-head 1 2 into the ot'iset 11 of chamber l the try-pass passage 8 is out off and the water in the ehanrber -l serves as a bearing to prevent further upward thrust of the impeller.

I i t in; ott'set"eoneentrie with said shaft:

This leakage into 1 chamber 4 will tend to bring the pressures on the impeller to equilibrium whenever the offset or head 12- eut's'oif the suction through by-pass 8. from chamber 13 past. the head 7 into the suetion 2, will simply pass through the impeller again.

What I claim is:

1. A vertical een trifngal pump comprising an axiall vmovable rotary impeller. a shaft therefor. a shell having" a bottom intake and peripheral outlet and provided at the top with a suetion chamber of greater eross-st etional area than the intake. said chamber havim. an upwardlrextendtny; offset concentric with said shal't there belng a passage connecting said otTset with the intake: said impeller being furnished with a head working in said ot't'set a head working in the intake, and a head working in the ehamher having the offset throughout tlte portion thereof within the periphery ot said lasenamed head.

2. vertical centrifugal pump eomprisim: an axiallymovahle rotary impeller. a shaft tltei'et'or. a shell haung a bottom intake and peripheral outlet and provided at the top with a stn'tion ehamher'ol' gr tter ero. eetional area thanthe intake. said ehalnher having an npwnrdly-extvntlthere being a eonduit external to the shell of the pump eonneeting' the top ot said ol'lset with the intake: said impeller being t'nrnished with a head working in said offset. a head wot-kite: in the intake, and a head wot-kin; in the ehaniher having the offset; the impeller helng impert'orate throughout the portion thereof within the periphery of said lastnatnetl The leakage the impeller ltt'illu' itn wrl'orate' 

